长喙毛茛泽泻的大小孢子发生及雌雄配子体发育

长喙毛茛泽泻（ＲａｎａｌｉｓｍａｒｏｓｔｒａｔｕｍＳｔａｐｆ）花药壁的发育属单子叶型，绒毡层为周原质团型．花粉母细胞减数分裂时的胞质分裂为连续型，四分体呈左右对称式排列，个别为交工型．成熟花粉为３细胞型，双珠被，薄珠心，倒生胚珠．大孢子母细胞由孢原细胞直接发育而来，成熟胚囊为８核组成的７细胞胚囊，两个极核在受精前不融合成次生核

MICROSPOROGENESIS,MEGASPOROGENESIS AND THE DEVELOPMENT OF MALE AND FEMALE GAMETOPHYTE IN RANALISMA ROSTRATUM STAPF

The anther wall development of Ranalisma rostratum follows the monocotyledonous type.The tapetum is the periplasmodial type. The cytokinesis of pollen mother cell in meiosis is the successive type.The arrangment of the microspores in tetrad is isobilateral,rarely decussate.The mature pollen grain belongs to the 3-cell type. The ovule is bitegminous, tenuinucellate and anatropous.The megaspore mother cell originates directly from the single archesporial cell. The mature embryo sac consists of 7 cells including 8 nuclei and con forms to the Allium type.Before fertilization, two polar nuclei do not fuse into a secondary nucleus.